MARTIN KASTE, BYLINE: This shift has been going on for a while now. Previous polls already showed a new majority in favor of legalizing marijuana. But in this survey, you also see changing attitudes toward harder drugs.

Carroll Doherty is Pew's director of political research. What strikes him is that two-thirds of respondents said they'd rather see the government focus on offering treatment to users of cocaine and heroin. Only 26 percent favored prosecution.

CARROLL DOHERTY: From there, you see that the public is really supportive of - or moving away from kind of a punitive approach to some of these drug use issues.

KASTE: And the politicians are following. By Pew's count, 30 states have eased penalties for drug possession over the past four years. And this isn't happening only in the country's more liberal precincts. Marc Levin is with the conservative Texas Public Policy Foundation. They did a poll a few months ago and found some similar attitudes.

MARC LEVIN: Some of the highest numbers were among Tea Party Republicans, in terms of the question: Should we divert low-level drug offenders to alternatives?

KASTE: Still, this doesn't mean that we're in the middle of a smooth, bipartisan policy shift. Levin says he's still seeing pockets of powerful resistance. He cites Louisiana, where the Sheriffs' Association is lobbying for tougher minimum prison terms for heroin users.

LEVIN: Nearly all the nonviolent ones are housed in parish jails run by the sheriff. And the sheriffs receive state money for every inmate. So they have a huge financial interest in keeping up the high levels of incarceration.

KASTE: At the Pew Center, Carroll Doherty says their survey does not show that people are less worried about drugs. The broad level of concern seems roughly stable, 32 percent call drug abuse a crisis nationally. What has changed, he says, is the racial dynamic.

DOHERTY: Lower-income whites, compared to 2001, many more are saying it's a crisis. African-Americans are holding a little bit more steady on that question.

KASTE: As drug abuse is perceived more as an equal-opportunity scourge, the broader public seems to have concluded that prison is not the answer, after all.